pci: Eliminate redundant PCIDevice::bus pointer

The bus pointer in PCIDevice is basically redundant with QOM information.
It's always initialized to the qdev_get_parent_bus(), the only difference
is the type.

Therefore this patch eliminates the field, instead creating a pci_get_bus()
helper to do the type mangling to derive it conveniently from the QOM
Device object underneath.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Eduardo Habkost <ehabkost@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel@redhat.com>
Reviewed-by: Peter Xu <peterx@redhat.com>

1 files changed, 3 insertions, 3 deletions

diff --git a/hw/pci/pci_bridge.c b/hw/pci/pci_bridge.c
index a47d257149..b2e50c36a0 100644
--- a/hw/pci/pci_bridge.c
+++ b/hw/pci/pci_bridge.c
@@ -183,7 +183,7 @@ static void pci_bridge_init_vga_aliases(PCIBridge *br, PCIBus *parent,
 static PCIBridgeWindows *pci_bridge_region_init(PCIBridge *br)
 {
     PCIDevice *pd = PCI_DEVICE(br);
-    PCIBus *parent = pd->bus;
+    PCIBus *parent = pci_get_bus(pd);
     PCIBridgeWindows *w = g_new(PCIBridgeWindows, 1);
     uint16_t cmd = pci_get_word(pd->config + PCI_COMMAND);
 
@@ -214,7 +214,7 @@ static PCIBridgeWindows *pci_bridge_region_init(PCIBridge *br)
 static void pci_bridge_region_del(PCIBridge *br, PCIBridgeWindows *w)
 {
     PCIDevice *pd = PCI_DEVICE(br);
-    PCIBus *parent = pd->bus;
+    PCIBus *parent = pci_get_bus(pd);
 
     memory_region_del_subregion(parent->address_space_io, &w->alias_io);
     memory_region_del_subregion(parent->address_space_mem, &w->alias_mem);
@@ -339,7 +339,7 @@ void pci_bridge_reset(DeviceState *qdev)
 /* default qdev initialization function for PCI-to-PCI bridge */
 void pci_bridge_initfn(PCIDevice *dev, const char *typename)
 {
-    PCIBus *parent = dev->bus;
+    PCIBus *parent = pci_get_bus(dev);
     PCIBridge *br = PCI_BRIDGE(dev);
     PCIBus *sec_bus = &br->sec_bus;